A new study of the DNA of Tibetans has looked at the gene underlying their ability to live in the low-oxygen conditions at high altitudes. It found that this gene has come from an unexpected source – the…

We humans had sex with Neandertals; we bonked the relatives of Neandertals; we got down and dirty with members of an as-yet unrecognised African population; and we, of course, got jiggy with each other…